Copper line erosion?

[Jim Luttrall]

Just did a 2006 McMansion with twin 50 water heaters and circulator pump with the master bath and seldom used jetted tub at the farthest point from the heaters. I suspect the master bath is where the return line for the circulator pump originates.
There was a large amount of sediment and ugly water when I filled the tub but clean and clear everywhere else.
I suspect the circulator pump is causing sediment to collect in a dead end pipe at the tub with the possibility of erosion of the pipes from the circulating hot water.
Any thoughts?

http://www.taco-hvac.com/uploads/FileLibrary/100-41.pdf

Do not oversize the pump or high velocity noise and erosion corrosion of system piping may result.

[Scott Patterson]

Did the water ever run clear at the master tub?

I assume the house was not occupied.

[Jim Luttrall]

Yep, clear water after the first filling.
The house was occupied but the seller did report that they rarely use the tub.

[Scott Patterson]

Could be at the end of the line, but with a circulation pump the water is always moving so I would not think that it would have a chance to collect in any place other than the water heaters.

One of those I don't know things we come across from time to time......

[Daniel Leung]

Yep, clear water after the first filling.
The house was occupied but the seller did report that they rarely use the tub.
Jim, that is the only reason. It is quite common to have the dirty water at the begining of first filling, every time the answer from the owners are the same - rarely use the tub.

[Jim Luttrall]

Well, I punted it to a competent plumber with experience in circulating system and a web address for info. My thought was the return line likely taps off the line in the master bath (could not see it - slab foundation) with the tub line below the tee so that the dead line acts like a sediment trap. Once I open the faucet, I just cleaned out the sediment trap.
My issues is that with this 2006 house with occasional tub use I would not expect to find this much sediment.
I did not open the tank drains, but I wonder what they look like?

[Billy Stephens]

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Yep, clear water after the first filling.

The house was occupied but the seller did report that they rarely use the tub.
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Could have a piece of galvanized ( nipple ) as a connector ( what the Installer had on the Truck that Day ) and the discolored water is a sign of rust being flushed from the Supply line.
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[Jim Luttrall]

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Could have a piece of galvanized ( nipple ) as a connector ( what the Installer had on the Truck that Day ) and the discolored water is a sign of rust being flushed from the Supply line.
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Yep, could have been, but galvanized is scarce as hen's teeth around here in anything built in the last 30+ years. Also, I'm doubting that galvanized would rust much in less than three years.
I could see most of the pipe coming out of the slab to the unit but it is possible a galvanized nipple was hiding there somewhere.

[Billy Stephens]

Also, I'm doubting that galvanized would rust much in less than three years.

I could see most of the pipe coming out of the slab to the unit but it is possible a galvanized nipple was hiding there somewhere.
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What is that Tee Connector made of?

( rarely used in 3 years could rust )
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